Variation In Fatty Acid Composition Research Articles

Saturated and Polyunsaturated Fatty Acids Rich Populations of Prinsepia utilis Royle in Western Himalaya.

The study aims to identify the fatty acid composition in Prinsepia utilis seeds collected from diverse populations of Western Himalaya, India. The seeds contained higher saturated fatty acid (SFA-43.09%; Average of all populations) followed by polyunsaturated fatty acid (PUFA - 29.57%) and monounsaturated fatty acid (MUFA - 25.53%), however variations among growing populations was measured. The correlation analysis reveals a significant (p < 0.05) negative connection between 10-Octadecenoic acid methyl ester (FA1), and altitude. Edaphic factors like available nitrogen showed significantly (p < 0.05) but the negative correlation with cis-11-Eicosenoic acid, methyl ester (FA10; p < 0.001), Docosanoic acid, methyl ester (FA11; p < 0.05), Heptadecanoic acid, methyl ester (FA14; p < 0.05), and Tricosanoic acid, methyl ester (FA29; p < 0.05). Antioxidant activity did not show any variation in the seed oil of different populations but varied among the concentrations (5-50 µL) used. IC50 values of DPPH activity was significantly (p < 0.05) varied connect ranged from 11.31-24.21 µL/mL among the different populations. These variations in fatty acid composition and IC50 values of the DPPH activity can be one of the indicators for selecting a promising population that would be harnessed for its potential in nutraceuticals and cosmeceuticals industries.

Genome-wide approaches delineate the additive, epistatic, and pleiotropic nature of variants controlling fatty acid composition in peanut (Arachis hypogaea L.).

The fatty acid composition of seed oil is a major determinant of the flavor, shelf-life, and nutritional quality of peanuts. Major QTLs controlling high oil content, high oleic content, and low linoleic content have been characterized in several seed oil crop species. Here, we employ genome-wide association approaches on a recently genotyped collection of 787 plant introduction accessions in the USDA peanut core collection, plus selected improved cultivars, to discover markers associated with the natural variation in fatty acid composition, and to explain the genetic control of fatty acid composition in seed oils. Overall, 251 single nucleotide polymorphisms (SNPs) had significant trait associations with the measured fatty acid components. Twelve SNPs were associated with two or three different traits. Of these loci with apparent pleiotropic effects, 10 were associated with both oleic (C18:1) and linoleic acid (C18:2) content at different positions in the genome. In all 10 cases, the favorable allele had an opposite effect-increasing and lowering the concentration, respectively, of oleic and linoleic acid. The other traits with pleiotropic variant control were palmitic (C16:0), behenic (C22:0), lignoceric (C24:0), gadoleic (C20:1), total saturated, and total unsaturated fatty acid content. One hundred (100) of the significantly associated SNPs were located within 1000 kbp of 55 genes with fatty acid biosynthesis functional annotations. These genes encoded, among others: ACCase carboxyl transferase subunits, and several fatty acid synthase II enzymes. With the exception of gadoleic (C20:1) and lignoceric (C24:0) acid content, which occur at relatively low abundance in cultivated peanuts, all traits had significant SNP interactions exceeding a stringent Bonferroni threshold (α = 1%). We detected 7682 pairwise SNP interactions affecting the relative abundance of fatty acid components in the seed oil. Of these, 627 SNP pairs had at least one SNP within 1000 kbp of a gene with fatty acid biosynthesis functional annotation. We evaluated 168 candidate genes underlying these SNP interactions. Functional enrichment and protein-to-protein interactions supported significant interactions (P-value < 1.0E-16) among the genes evaluated. These results show the complex nature of the biology and genes underlying the variation in seed oil fatty acid composition and contribute to an improved genotype-to-phenotype map for fatty acid variation in peanut seed oil.

The impact of weather conditions in different years on the biochemical composition of linseed oil

Background. Linseed oil is a versatile product with varying biochemical composition. Linseed breeding is aimed at producing cultivars with different chemical properties in their oil. The crop is widespread but the environment has a great effect on its fatty acid biosynthesis.Materials and methods. The impact of weather conditions on the variations in fatty acids composition was studied. Twenty linseed cultivars and accessions of diverse origin and with varying oil composition from the VIR collection were grown in Tomsk Province in 2016–2018. The content of 15 fatty acids (lauric, myristic, palmitic, palmitoleic, margaric, stearic, oleic, cis-vaccenic, linoleic, linolenic, arachidic, eicosenic, arachido nic, behenic, and lignoceric) was assessed in linseed oil using gas–liquid chromatography.Results. The tested material presented a wide diversity of genes controlling different steps of fatty acids biosynthesis and genetic mechanisms involved in the responses to the changing environment. The analysis of variance proved that the content of oleic, linoleic, linolenic and lignoceric acids was controlled solely by the genotype. The content of palmitic and stearic acids was influenced by both the genotype and environment. The synthesis of lauric and cis-vaccenic acids was significantly affected by the weather. Practically all acids, except linoleic and linolenic ones, showed a very high random variation, which in our experiment included genotype × environment interaction. The accessions differed in the range of variation in their characters under diffe rent conditions. There was no definite regularity in the hanges of fatty acid content in the tested genotypes during 3 years.Conclusion. The assessed genotypes probably possess different regulatory mechanisms for fatty acid biosynthesis. Thus, they present a diverse stock for further investigations into fatty acid biosynthesis and for the development of new linseed cultivars widely adaptable to environmental conditions.

Impact of intermittent frying on chemical properties, fatty acid composition, and oxidative stability of 10 different vegetable oil blends

Impact on chemical properties, viscosity, oxidative stability, and fatty acid composition (FAC) of 10 vegetable oil blends (VOBs) following intermittent frying of chickpea splits was studied. The peroxide (PV), p-Anisidine (p-AV), acid (AV) value, and viscosity of VOBs increased, while oxidative stability index (OSI) decreased by increasing frying cycles (FCs). VOB-3 and VOB-7 exhibited a minimum change in PV, AV, p-AV, viscosity, and OSI with an increment in FCs. Oil uptake increased with an increment in FCs and the lowest change observed in VOB-3 (6.0%–13.7%). VOB-7, VOB-8, and VOB-6 exhibited lower changes in ω6/ω3 ratio, saturated and unsaturated fatty acids contents, respectively with an increment in FCs. VOB-5 and VOB-9 exhibited higher variation in FAC and FTIR peaks while atherogenic and thrombogenic index of VOBs varied slightly with an increment in FCs. Based on the results, VOB-3 and VOB-7 were found suitable for intermittent frying of chickpea splits. Practical applications Vegetable oil blends suitable for deep fat frying were identified by comparing quality and stability characteristics of 10 VOBs during intermittent frying of chickpea splits. VOB-3 (CNO + SBO [80:20]) and VOB-7 (CNO + RBO + SBO [60:20:20]) exhibited minimum changes in chemical properties, viscosity, and OSI with an increment in FCs and had balanced FAC (ω6/ω3 ratio). Thus, VOB-3 and VOB-7 are suitable for intermittent frying among the studied VOBs.

Effects of growing region and maturity stages on oil yield, fatty acid profile and tocopherols of Pistacia atlantica Desf. fruit and their implications on resulting biodiesel

Pistacia atlantica Desf. fruit oil may be considered as a feedstock which is low cost and does not compete with food crops for biodiesel production. The aim of this paper was to investigate the effect of the variation in fatty-acid composition and oil accumulation in developing P. atlantica fruits on the resulting biodiesel properties. Samples were collected from two Algerian sites, i.e. Ain oussera and Laghouat. Gas-liquid chromatography revealed that the oleic acid (51.6–55.4% of fatty acids) was the major component, followed by linoleic acid (21.9–29.4%), and palmitic acid (12.7–19.4%). The highest tocopherol isomer contents were observed in the immature stage (200–256 μg g−1 oil). The quality of the biodiesels synthesized from immature and mature P. atlantica fruit oils was tested according to the international standards. All biodiesel samples exhibited a high energy content with a higher heating value (HHV) of 40 MJ kg−1. Meanwhile, the cetane number, long chain saturation factor, degree of unsaturation, oxidative stability and density were in the ranges 53–55, 4.3–5.6, 101–113, 3.4–3.8 h, and 852–862 kg m−3, respectively. The cold flow behavior of biodiesel was assessed through the cloud point (CP) and the cold filter plugging point (CFPP). The CP value ranged from −4.5 to −2.3 °C, and CFPP from −7.1 to −4.9 °C. The above fuel properties comply with the limits imposed by the EN 14214–08, GB/T 20828–07 and ASTM D6751-2010 standards, showing a promising source for biodiesel production in Algeria.

Taxonomic, Temporal, and Spatial Variations in Zooplankton Fatty Acid Composition in Puget Sound, WA, USA

Fatty acid (FA) content and composition of zooplankton in Puget Sound, Washington (USA) was studied to investigate the nutritional quality of diverse zooplankton prey for juvenile salmon (Oncorhynchus spp.) in terms of their essential fatty acid (EFA) content. The study focus was on eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (ARA) as these are key FA needed to maintain growth and development of juvenile fish. The different zooplankton taxa varied in their FA composition. Much of the variation in FA composition was driven by 18:1ω9 (a biomarker of carnivory), ARA, DHA, and FA characteristic of diatoms, which are linked to zooplankton diet sources. Gammarid and hyperiid amphipods contained the highest amount of EFA, particularly the gammarid amphipod Cyphocaris challengeri, while shrimp and copepods had much lower EFA content. Crab larvae, which are important prey for juvenile salmon in Puget Sound, had intermediate EPA + DHA content and the lowest DHA/EPA ratio, and were rich in diatom biomarkers. Temporal and spatial trends in zooplankton lipids were less apparent than the taxonomic differences, although the EFA content increased from spring to summer in Cancridae zoeae and the amphipod C. challengeri. These results on taxon-specific EFA content provide baseline information on the nutritional quality of zooplankton that can be applied in food web models. Combining zooplankton fatty acid data (quality) with taxon-specific zooplankton biomass data (quantity) enables development of new, sensitive indicators of juvenile fish production to help assess recent declines in salmon production in the Pacific Northwest and predict future adult returns.

Seasonal variation in fatty acid and triacylglycerol composition of bovine milk fat

The aim of this study was to assess the effects of seasonal variation on the changes of the fatty acid (FA) and triacylglycerol (TAG) composition of bovine milk fat (MF) in a nonseasonal milking system. Weekly milk samples were collected from 14 dairy factories and pooled per week as representative samples of the average Dutch bovine milk. The sample collection started in May 2017 and finished in April 2018, resulting in a total of 52 samples, corresponding to each week of the year. The samples were analyzed for MF content (%) and FA and TAG composition using gas chromatography with flame-ionization detection. The increased intake of C18:3 cis-9,12,15 through grass feeding in spring and summer was associated with major changes in MF FA composition, including reduced proportions of de novo synthesized FA and presence of several rumen biohydrogenation products and conjugated linoleic acid isomers in MF. These changes in seasonal FA composition had an effect on TAG seasonal variation. The TAG seasonal variation showed that all TAG groups were significantly different between months. The low molecular weight and the medium molecular weight TAG groups increased in winter and decreased in summer, whereas the high molecular weight TAG groups increased in summer and decreased in winter. Based on pooled monthly samples, MALDI-TOF-mass spectrometry allowed the analysis of even- and odd-chain TAG species in MF based on their total carbon number and number of double bonds. These analyses indicated saturated TAG species to be greatest in winter, whereas monounsaturated, polyunsaturated, and odd-chain TAG species were greatest in summer. Our study showed that TAG seasonal variation in a nonseasonal milking system is influenced by the variation in FA composition throughout the seasons.

Isolation of fast-growing thraustochytrids and seasonal variation on the fatty acid composition of thraustochytrids from mangrove regions of Navi Mumbai, India

This study was aimed to isolate fast-growing thraustochytrids and the influence of seasonal variation in fatty acid composition from the mangrove habitat. The thraustochytrids were isolated from fallen yellowish or green mangrove leaves, in four seasons, including winter, summer, rainy, and post rainy season in one year. The thraustochytrids were analyzed for biomass production, total lipid content, and fatty acid profile. The thraustochytrid isolates showed biomass yield and total lipid content in the range of 14.12 ± 0.69 to 22.98 ± 0.53 g/L and 34.98–58.86% per dry cell weight, respectively. The isolates showed two dominant fatty acids, palmitic acid (PA) as saturated fatty acid (SFA) and docosahexaenoic acid (DHA) as long-chain polyunsaturated fatty acids (LC-PUFA) in total fatty acid (TFA) content. The significant differences (P < 0.05) were observed for seasonal variations in SFA and DHA content in summer isolates and winter isolates. The maximum DHA content with 47.12% of TFA, recorded in winter (January) isolates and summer (April) isolates with SFA 68.82% of TFA. The results from this study were verified the hypothesis that the presence of high DHA producing thraustochytrids in lower temperature season in the same habitat. These findings have also emphasized the role of the environmental temperature conditions and the importance of thraustochytrid fatty acid composition as a dietary biomarker. Also, it revealed the ecological significance of thraustochytrid in DHA enrichment in the food web of the marine ecosystem. These findings could be useful while isolating thraustochytrids according to seasons for industrial application for omega 3 fatty acids and biodiesel production.

Seasonal Variation of Fatty Acid Composition in Muscle Total Lipids of Male and Female Individuals of Alburnus tarichi

In our study, sixteen types of fatty acids were determined as a result of muscle tissue analysis, among which, out of saturated fatty acids,16:0; out of monounsaturated ones, 16:1n-7 and 18:1n-9; and out of polyunsaturated ones, 20:5n-3 and 22:6n-3 were major. Other fatty acids were found in trace amounts. Out of saturated fatty acids, 16:0 was found to be 14.94% on average in females and 15.34% in males. 16:0 increased in August in both sexes. The ratio of 18:0 was at the level of 4% in both sexes. Furthermore, this component was found to fluctuate depending on the months. 16:1n-7 was 13.28% in female individuals and 13.16% in males. The ratio of 18:1n-9, which was the other major MUFA component, was 21.67- 25.40% in females, while it was 20.63-27.73% in male individuals. It was observed that this component decreased in both sexes in February, while it increased in females in October and in male fish in August. The ratio of 20:5n-3, which is another polyunsaturated component, did not change significantly among months, with an average value of 11.60% in females and 10.93% in males. The ratio of 22:6n-3, which was found as the other major one, decreased in October with a rate of 12.61% in females and 12.67% in males and showed a similar distribution in the other months. In the analyses, the ratio of ω3/ω6, which is important in terms of the nutritional value of fish, was determined as 3.97 on average in females and 3.88 on males. These components increased in December in both sexes, whereas they decreased in February. We determine ΣSFA increased in August in both sexes, and ΣMUFA increased in October, but ΣPUFA decreased in the same month. In all analyzed months, ΣMUFA and ΣPUFA were more than ΣSFA in both sexes.

Phospholipid fatty acids from Colombian Caribbean sea sponges

Five demosponges belonging to the order Axinellida: Axinella corrugata, Dragmacidon alvarezae, Dragmacidon reticulatum, Ptilocaulis walpersi, Myrmekioderma rea and one sponge belonging to the order Scopalinida: Scopalina ruetzleri were analyzed to assess their fatty acid composition in the phospholipid fraction. Additionally, the seasonal and intraspecific variation in fatty acids composition was assessed in M. rea and D. alvarezae. Fatty acid identification was conducted using an HRGC-MS with an ECL value of methyl ester derivatives, and analyzing their mass spectra. To confirm double bound location, N-acylpyrrolidide derivatives were used studying their mass spectra. In total, 83 fatty acids were identified with chain lengths ranging from C14 to C32. Interestingly, brominated fatty acids were identified, previously suggested for sponges. Polybranched fatty acids such as 4,8,12-trimethyltridecanoic acid (4,8,12-TMTD) and 3,7,11,15-tetramethylhexadecanoic (phytanic acid) were found, without a clear distribution pattern. A predominance of iso-acids (i-15:0 and i-17:0) on anteiso acids were observed. Some seasonal variations in fatty acid (FA) compositions for M. rea and D. alvarezae were observed. The hierarchical Clusters Analysis (HCA) showed that the FA composition was species-specific but not informative at the family or order level.

Analysis of Cymbopogon Citratus, Pinus sylvestris and Syzygium cumini biodiesel feedstocks for its fatty acid composition

Rapid depletion of fossil fuel and increased demand for petroleum products in energy and transportation sector motivated the researchers to find a substitution for petroleum diesel. Biodiesel is one among the alternate to this crisis. Biodiesel is a combined mixture of fatty acid alkyl esters obtained by the reaction of triglycerides of vegetable or animal origin with alcohol in the presence of a catalyst. The fatty acid profile influences the overall properties of the biodiesel. The properties of individual fatty acid depend on the occurrence of double bonds, fatty acid chain length and branching. Better understanding of the fatty acid composition and correlating the fuel properties is of utmost importance in improving the optimal performance. In the present study, feedstocks of Cymbopogon citratus, Pinus sylvestris and Syzygium cumini is analysed for its fatty acid composition study using Gas Chromatography assisted with mass spectrometry. Based on GC–MS Analysis, fifteen types of fatty acids in Cymbopogon citratus, Pinus sylvestris and Syzygium cumini oil methyl esters were analysed and defined; all these esters are amalgamations of saturated and unsaturated fatty acids. The variation in fatty acid compositions affects the properties of the esters. GC–MS synthesis showed that methyl, ethyl esters free from dirt for the three feedstocks. Few impurities like mainly mono-, di- and triglycerides were found.

Seasonal variation of fatty acid composition, tocopherol content and antioxidant activity of lipid extracts from Centaurea sp.

The changes in fatty acid (FA) composition, and total tocopherol content (TTC) of leaves, roots and roots' bark of Cenaurea sp. grown on the Algerian coast were studied. Moreover, the change within the same season in antioxidant activity of lipid fractions was also measured using the DPPH free radical scavenging activity assay. Results showed quantitative and qualitative changes of the contents of saturated, monounsaturated, polyunsaturated fatty acids and TTC from January until June with different patterns for the different plant parts. The highest TTC were obtained for both roots and roots' bark, and changed differently with the month of collection. The antioxidant IC50 values also showed different pattern changes during the season for roots and roots' bark. Cluster analysis using Agglomerative Hierarchical Clustering showed differences in FA amounts for C18:2 and C18:3 between roots’ bark and both roots and leaves parts, which were totally independent of the month of collection.

Comparison of fatty acid composition, phytochemical profile and antioxidant activity in four flax (Linum usitatissimum L.) varieties

The present study evaluates variations among flaxseed varities in terms of fatty acid composition, phytochemical profile, and antioxidant activity determined by oxygen radical absorbance capacity (ORAC), 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and ferrous ion reducing antioxidant power (FRAP) assays. Significant variations in fatty acid composition, phenolic acids and lignan were observed in flaxseed varieties from different countries. Among them, unsaturated fatty acids accounted over 4/5 of total fatty acid content. The highest ratio of linolenic acid of total fatty acid was observed in USPEA, whereas the lowest one was found in Yexiao. USPEA showed the highest content of total phenolics, as well as flaxseed lignan. In general, total phenolics appeared to be the main contributors of antioxidant capacity of flaxseed, which presented significant positive correlation. Our study revealed that both cultivar and origin of seed significantly affected fatty acid composition, phenolic acids, lignans and subsequent antioxidant activity of flaxseed. These results provided new aspects of breeding resources of flaxseed cultivars by presenting their quality specification and possible commercial value.

Modeling fatty acids for dairy cattle: Models to predict total fatty acid concentration and fatty acid digestion of feedstuffs

Development of predictive models of fatty acid (FA) use by dairy cattle still faces challenges due to high variation in FA composition among feedstuffs and fat supplements. Two meta-analytical studies were carried out to develop empirical models for estimating (1) the total FA concentration of feedstuffs, and (2) the apparent total-tract digestibility of total FA (DCFATTa) in dairy cows fed different fat types. In study 1, individual feedstuff data for total crude fat (EE) and FA were taken from commercial laboratories (total of 203 feeds, 1,170,937 samples analyzed for total FA, 1,510,750 samples analyzed for total EE), and data for FA composition were collected from the Cornell Net Carbohydrate and Protein System feed library. All feedstuffs were grouped into 7 classes based on their nutritional components. To predict total FA concentration (% of dry matter) for groups of feeds, the total EE (% of dry matter) was used as an independent variable in the model, and all models were linear. For forages, data were weighted using the inverse of the standard error (SE). Regression coefficients for predicting total FA from EE (% of dry matter) were 0.73 (SE, 0.04), 0.98 (0.02), 0.80 (0.02), 0.61 (0.04), 0.92 (0.03), and 0.93 (0.03), for animal protein, plant protein, energy sources, grain crop forage, by-product feeds, and oilseeds, respectively. The intercepts for plant protein and by-product groups were different from zero and included in the models. As expected, forages had the lowest total FA concentration (slope = 0.57, SE = 0.02). In study 2, data from 30 studies (130 treatment means) that reported DCFATTa in dairy cows were used. Data for animal description, diet composition, intakes of total FA, and DCFATTa, were collected. Dietary sources of fat were grouped into 11 categories based on their fat characteristic and FA profile. A mixed model including the random effect of study was used to regress digested FA on FA intake with studies weighted according to the inverse of their variance (SE). Dietary intake of extensively saturated triglycerides resulted in markedly lower total FA digestion (DCFATTa = 44%) compared with animals consuming unsaturated FA, such as Ca-salts of palm (DCFATTa = 76%) and oilseeds (DCFATTa = 73%). Cows fed saturated fats had lower total FA digestion among groups, but it was dependent on the FA profile of each fat source. The derived models provide additional insight into FA digestion in ruminants. Predictions of total FA supply and its digestion can be used to adjust fat supplementation programs for dairy cows.

Variations in fatty acid composition and antioxidant content in olive fruits as a result of the application of phytoregulators to the olive tree (Olea europaea L.)

ABSTRACT A new procedure to minimize the degradation of fatty acids and polyphenols during the olive storage is here proposed. This procedure is based on pre-harvest treatments of Arbequina and Picual olive trees with methyl jasmonate and abscisic acid. As a result, total phenolic content increased in all treated Arbequina olives as compared with controls. In contrast to Arbequina, only abscisic acid resulted in total phenolic content increase in Picual olives. Regarding the antioxidant activity, neither of the phytoregulators was effective. Fatty acid composition was also affected by both of them in Arbequina and Picual. Saturated fatty acid decreased with both methyl jasmonate and abscisic acid whereas unsaturated fatty acids increased significantly in treated olives. Olives with higher antioxidant activity exhibited higher unsaturated/saturated fat ratio. The application of phytoregulators to olive tree can be interesting to the oil industry particularly when a delay in oil processing occurs and olives have to be stored.

Natural Variation in Fatty Acid Composition of Diverse World Soybean Germplasms Grown in China

Soybean (Glycine max L. Merr.) is one of the most important crops in the world. Its major content of vegetable oil made it widely used for human consumption and several food industries. To investigate the variation in seed fatty acid composition of soybeans from different origins, a set of 633 soybean accessions originated from four diverse germplasm collections—including China, United States of America (USA), Japan, and Russia—were grown in three locations, Beijing, Anhui, and Hainan for two years. The results showed significant differences (P &lt; 0.001) among the four germplasm origins for all fatty acid contents investigated. Higher levels, on average, of palmitic acid (PA) and linolenic acid (LNA) were observed in Russian germplasm (12.31% and 8.15%, respectively), whereas higher levels of stearic acid (SA) and oleic acid (OA) were observed in Chinese germplasm (3.95% and 21.95%, respectively). The highest level of linoleic acid (LA) was noticed in the USA germplasm accessions (56.34%). The largest variation in fatty acid composition was found in LNA, while a large variation was observed between Chinese and USA germplasms for LA level. Maturity group (MG) significantly (P &lt; 0.0001) affected all fatty acids and higher levels of PA, SA, and OA were observed in early maturing accessions, while higher levels of LA and LNA were observed in late maturing accessions. The trends of fatty acids concentrations with different MG in this study further provide an evidence of the importance of MG in breeding for such soybean seed components. Collectively, the unique accessions identified in this study can be used to strengthen the soybean breeding programs for meeting various human nutrition patterns around the globe.

Fatty Acid Composition of New Zealand Forage Finished Beef Compared to US Grain Fed Beef

ObjectivesThe objective of this study was to evaluate differences in fatty acid (FA) composition of NZ beef finished on fodder beet (Beta vulgaris subsp. vulgaris L.; FB) or traditional grass diets and US grain-finished beef.Materials and MethodsStrip loins (n = 240) were selected from a commercial abattoir in NZ representing two feeding treatments (FB, non-FB) and expected low and high eating quality (primarily based on marbling) following a nationwide feeding trial to finish beef steers using FB. Selection resulted in four treatments: FB low quality (FBL), FB high quality (FBH), non-FB low quality (NFBL), and non-FB high quality (NFBH). Additionally, sides of beef (n = 120) representing USDA Top Choice (TCH) and Select (SEL) were sourced from a commercial abattoir in the US. Loins were fabricated prior to 21 d postmortem to isolate the longissimus lumborum (LL); these were sliced into 2.5 cm steaks, vacuum packaged, and stored at 2–4°C until 21 d or 35 d postmortem and frozen on the appropriate day. Lipids were extracted from a subset of samples via chloroform: methanol extraction then separated into polar and neutral fractions. Fatty acid methyl esters were evaluated using GC-FID. Data were analyzed with a 2-way ANOVA at a significance level of α = 0.05 and treatment, aging, and the respective interaction as fixed effects.ResultsAging influenced percent saturated FA (%SFA; P &lt; 0.01), monounsaturated FA (%MUFA; P &lt; 0.01), and polyunsaturated FA (%PUFA; P = 0.01). An increase in %MUFA and %PUFA at 35 d compared with 21 d (P &lt; 0.01) corresponded with a decrease in %SFA at 35 d (P &lt; 0.01). Treatment also influenced %PUFA (P &lt; 0.01). NFBL contained the greatest %PUFA (P &lt; 0.05). TCH and FBH contained less %PUFA than all treatments except SEL (P &gt; 0.05). Treatment and aging also affected palmitic and stearic acids (P &lt; 0.01), which make up the greatest portion of SFA. The proportion of palmitic acid was least in SEL (P &lt; 0.05) and greater in FBH than NFBH and TC (P &lt; 0.05). The US treatments had lower proportions of stearic acid than NZ treatments (P &lt; 0.05). Both palmitic and stearic acids were of greater proportions in 35 d samples than 21 d samples (P &lt; 0.05). Oleic acid contributes largely to total FA and was affected by the interaction of treatment and aging (P = 0.04). At 35 d, NZ treatments had greater proportions of oleic acid than at 21 d (P &lt; 0.05). The proportion of oleic acid was least in SEL at both aging times. Of the PUFA, linoleic was affected by treatment (P &lt; 0.05) and was greatest in SEL and TC (P &lt; 0.05); FB treatments had the lowest proportion of linoleic acid (P &lt; 0.05). Treatment and aging affected α-linolenic acid (P &lt; 0.01). NFBL and NFBH had a greater proportion than both FB and US treatments (P &lt; 0.05); both FB treatments had greater proportions of α-linolenic than US treatments (P &lt; 0.05). Proportion of α-linolenic acid was elevated with 35 d aging (P &lt; 0.05). Treatment affected proportions of long chain PUFA (P &lt; 0.05) with TCH and SEL having lower proportions than NZ treatments (P &lt; 0.05). Low quality NZ treatments had the greatest proportions of long chain PUFA (P &lt; 0.05).ConclusionWhile finishing diet does affect fatty acid composition of beef strip steaks, finishing on FB produces a similar FA composition to non-FB grass. Total lipid content is also responsible for variation in FA composition. As lipids oxidize during aging, a shift toward more unsaturated FA occurs, leading to a decrease in %SFA.

Seasonal variation of fatty acids composition of milk from grazing ewes in Thessaly, central Greece

The aim of this work was to evaluate the changes in fatty acids (FAs) profile and conjugated linoleic acid (CLA) concentration of milk from grazing ewes in winter (December and January) and spring (April and May) in Thessaly, central Greece. No significant changes (P&gt;0.05) in the physicochemical properties (pH and protein, lactose and total solids content) of winter and spring milk were observed. However, the fat content of spring milk was lower (P&lt;0.05) than the winter milk. The saturated FAs content of milk was not significantly changed (P&gt;0.05) during winter neither during spring, whereas the polyunsaturated FAs content was significantly changed (P&lt;0.05) in each of the four months examined. Nevertheless, in the ovine milk of spring, the saturated FAs content was significantly decreased (P&lt;0.05), but the monounsaturated and polyunsaturated FAs content was significantly increased (P&lt;0.05) as compared to that of winter milk. In contrast to the saturated FAs decrease in spring milk, the saturated stearic acid (C18:0) content showed a significant increase (P&lt;0.05) in the spring milk as compared to winter milk. In winter milk, the C18:2 cis-9, trans-11 CLA levels were 0.89±0.05 and 0.98±0.03g/100 g Fatty Acid Methyl Esters (FAMEs) in December and January, respectively, whereas, in spring milk, the CLA levels were significantly increased (P&lt;0.05) to 1.36±0.04 and 1.27±0.03g/100 g FAMEs in April and May, respectively. The atherogenicity index (AI) associated with proatherogenic and antiatherogenic FAs was found significantly (P&lt;0.05) lower in spring milk compared to winter milk.

Multivariate Genome-Wide Association Analyses Reveal the Genetic Basis of Seed Fatty Acid Composition in Oat (Avena sativa L.).

Oat (Avena sativa L.) has a high concentration of oils, comprised primarily of healthful unsaturated oleic and linoleic fatty acids. To accelerate oat plant breeding efforts, we sought to identify loci associated with variation in fatty acid composition, defined as the types and quantities of fatty acids. We genotyped a panel of 500 oat cultivars with genotyping-by-sequencing and measured the concentrations of ten fatty acids in these oat cultivars grown in two environments. Measurements of individual fatty acids were highly correlated across samples, consistent with fatty acids participating in shared biosynthetic pathways. We leveraged these phenotypic correlations in two multivariate genome-wide association study (GWAS) approaches. In the first analysis, we fitted a multivariate linear mixed model for all ten fatty acids simultaneously while accounting for population structure and relatedness among cultivars. In the second, we performed a univariate association test for each principal component (PC) derived from a singular value decomposition of the phenotypic data matrix. To aid interpretation of results from the multivariate analyses, we also conducted univariate association tests for each trait. The multivariate mixed model approach yielded 148 genome-wide significant single-nucleotide polymorphisms (SNPs) at a 10% false-discovery rate, compared to 129 and 73 significant SNPs in the PC and univariate analyses, respectively. Thus, explicit modeling of the correlation structure between fatty acids in a multivariate framework enabled identification of loci associated with variation in seed fatty acid concentration that were not detected in the univariate analyses. Ultimately, a detailed characterization of the loci underlying fatty acid variation can be used to enhance the nutritional profile of oats through breeding.

Lipid Droplets Mediate Salt Stress Tolerance in Parachlorella kessleri.

Microalgae are known to respond to salinity stress via mechanisms that include accumulation of compatible solutes and synthesis of antioxidants. Here, we describe a salinity-tolerance mechanism mediated by lipid droplets (LDs). In the alga Parachlorella kessleri grown under salt-stress conditions, we observed significant increases in cell size and LD content. LDs that were closely grouped along the plasma membrane shrank as the plasma membrane expanded, and some LDs were engulfed by vacuoles. Transcriptome analysis showed that genes encoding lysophospholipid acyltransferases (LPLATs) and phospholipase A2 were significantly up-regulated following salt stress. Diacylglycerol kinase and LPLAT were identified in the proteome of salt-induced LDs, alongside vesicle trafficking and plastidial proteins and histone H2B. Analysis of fatty acid composition revealed an enrichment of C18:1 and C18:2 at the expense of C18:3 in response to salt stress. Pulse-chase experiments further suggested that variations of fatty acid composition were associated with LDs. Acetate stimulation research further confirmed a positive role of LDs in cell growth under salt stress. These results suggest that LDs play important roles in salt-stress tolerance, through harboring proteins, participating in cytoplasmic component recycling, and providing materials and enzymes for membrane modification and expansion.